Foraging workers of the red imported fire ant, Solenopsis invicta, were observed to respond to the presence of hot dog slices. The ants detected the odor of this food lure from an overhead distance of at least 3 cm and possibly as far as 5 cm. In addition, more foraging ants accumulated over time underneath the lures compared to the nontreated check (no hot dog slice). The technique used could help develop food lures detectable by ants at greater distances to improve detection and management programs.

Enzymatic mechanisms indicating resistance were determined in the southern house mosquito, Culex quinquefasciatus Say, from Nuevo Leon, northeastern Mexico, after exposure to pyrethroids: trans-permethrin (92% trans-6% cis) 0.75%, bifenthrin (99%) 0.1%, cypermethrin (99%) 0.1%, deltamethrin (99%) 0.5%, and lambda-cyhalothrin (99.1%) 0.5%. Mosquitoes were collected from four municipalities in the north and center of the state of Nuevo Leon. Four groups of 25 female mosquitoes, 24 hours of age were exposed to insecticide doses pre-evaluated. After 50% of the mosquitoes had died, individuals were divided into alive and dead categories. With the individuals selected and a group of 100, 1-day old adult females from each location without exposure to the pyrethroids, biochemical tests were used to determine resistance-related activities of enzymes alpha- and beta-esterases, glutathione S-transferases, and mixed-function oxidases. The results were compared with those from a susceptible strain of southern house mosquito obtained after rearing for 25 generations in a laboratory. Biochemical assays showed elevated glutathione S-transferases and esterases, enzymes associated with resistance to pyrethroids.

The lifecycle of Bactericera cockerelli was evaluated on the tomato varieties ‘Charanda F1’ and ‘Rafaello’, under greenhouse conditions at the Colegio de Postgraduados, Campus Montecillo, Texcoco, Mexico, during October–December, 2009 and January–March, 2010. A line of B. cockerelli dating from 10 years ago free from agrochemical applications was used. The adults were kept in individual growth chambers. The parameters measured were average life expectancy (e_x), net reproductive ratio (R_o), time of generation (T), intrinsic natural increase ratio (r_m), finite increase ratio (λ), births (b), and mortality (d) in each of the varieties. For the October–December cycle, reproduction began at 34 days in the ‘Charanda F1’ variety, and at 41 days in January–March. The incubation period for the eggs was 7–13 days, with a nymphal period of 32–37 days in ‘Charanda F1’; in ‘Rafaello’, incubation took 8–10 days, with a nymphal period of 31–35 days. The lifecycle in Charanda F1 was 63–69 days, and was 68–70 days in Rafaello. The accumulated fecundity of the females was 3,426–3,200 eggs in Charanda F1 and 2,142–2,099 eggs in Rafaello.

We investigated predation by adult convergent lady beetle, Hippodamia convergens Guerin-Meneville, on English grain aphid, Sitobion avenae L., on wheat, Triticum aestivum L., plants in a laboratory arena and developed a functional response model for the number of aphids eaten by an adult female convergent lady beetle. We observed the foraging activity of 56 female convergent lady beetles, and a combined total of 1,167 plant visits by those beetles. Beetle hunger and the number of aphids per plant were significantly correlated with the time spent searching a wheat plant and the number of aphids eaten during the plant visit. Partial correlation coefficients for hunger after adjusting for the effect of the number of aphids per plant were not significant for the time spent searching a plant or for the number of aphids eaten during a plant visit. Among the variables measured, knowledge of the number of aphids per plant was sufficient for predicting searching time and predation. A Holling Type II functional-response model was developed and tested for convergent lady beetles foraging on English grain aphids. Comparison of the expected versus observed proportions of English grain aphids eaten showed no statistically significant bias in model predictions, thus indicating that the model provided a reasonable description of the functional response. However, variation in observed versus predicted predation rates was evident, which may reflect the inherent variability in all aspects of the foraging process by the beetles.

The efficacy of bioinsecticides that act by ingestion can be improved using phagostimulants that increase the consumption of the pathogen. Three biopolymers, gelatin, pectin, and corn starch, with five additive phagostimulants, maize spike, fresh maize cobs, alfalfa, sorghum leaves, and cabbage, were used to form 18 microencapsulant matrices. The matrices were evaluated for feeding preferences by beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae). Ten neonate larvae were given a choice between two different matrices or between one matrix and a small piece of fresh cabbage used as a check. Results showed that beet armyworm larvae preferred matrices of gelatin and pectin biopolymers and additives of cabbage powder or maize spike over fresh cabbage. The best microencapsulant agents were gelatin-cabbage and gelatin-maize spike, attracting 5.47 and 5.42 larvae, respectively. The larvae preferred fresh cabbage when given a choice between fresh cabbage and a biopolymer without any phagostimulant. Phagostimulants can be added to biopesticides to increase the consumption rate and kill more pests. Gelatin was the best biopolymer and the phagostimulants maize spike and cabbage were very palatable to beet armyworm larvae.

A total of 142 soil samples was collected from different Mexican states: Campeche (13), Michoacán (15), Nuevo León (25), San Luis Potosí (25), Sinaloa (17), Sonora (17), Tabasco (5), Tamaulipas (20), and Yucatán (5). Larvae of the greater wax moth, Galleria mellonella (L.), were used as bait to detect, trap, and multiply entomopathogenic fungi in vivo. Twenty-three percent of the soil samples processed were positive for the presence of entomopathogenic fungi according to the macroscopic and microscopic characteristics: Beauveria bassiana (Bals.-Criv.) Vuill. was detected in 12% (17 isolates), Metarhizium anisopliae (Metchnikoff) Sorokin in 1% (2 isolates), and Isaria fumosorosea (Wize) in 10% (14 isolates). Genetic variability of the fungi was analyzed using the sequences of internal transcribed ribosomal genes (ITS-5.8S-ITS2) and digested with the enzyme Haelll. PCR results generated fragments of 600 bp for B. bassiana and M. anisopliae, and more than 600 bp for I. fumosorosea. Both reference strains and field isolates produced similar restriction patterns. Genera of native entomopathogenic fungi were found in the diverse citrus areas of Mexico, opening the possibility for biological control of pests affecting citrus in each region.

A new species of Docosia Winnertz fungus gnat was discovered in western Michigan. Males and females were collected in mid-spring in a Malaise trap in a paper birch-red maple-black cherry woods adjacent to a black ash swamp and cattail marsh. Docosia walpurga Taber resembles Docosia dichroa Loew but male terminalia and female coloration indicate a specific difference instead. A remarkable and yet-unidentified empidid fly that seems to mimic the fungus gnat was found with the new species.